No Sound, nForce ALC650E

On TWO separate Asus A7N266-VM motherboards, installing Feisty or running it from the Live CD, there is no sound output. Both have line-out connected to the LCD monitor speakers. Both work correctly with Windows XP or Windows 2003.

These systems have Nvidia nForce chip-sets with the Realtec ALC650E driven by the snd_intel8x0 driver.

Initially I thought this was some kind of weird problem on one PC although I knew that in Windows the sound was fine. Via the Live CD I've confirmed the problem occurs on another system with the same motherboard. I've tested it with BIOS versions 1004, 1005, 1007, 1008 beta.

I tried installing Edgy and the same problem occurs with that, too. I posted the system configuration of the Edgy test in the forums at:

http://ubuntuforums.org/showthread.php?t=441420

What is strange is that Edgy can be tricked into playing sound (out the rear channels only) by using 4ch and 'duplicate front', but Feisty can't. I've tried every combination of mixer switches I can think of, both on Feisty and Edgy.

In 2ch mode, Audacity shows (via its monitor) that microphone and line-in are working and it can record from them. In 4ch mode + 'duplicate front', Edgy+Audacity can play sound out of the rear channels only.

$ uname -a
Linux tom 2.6.20-15-generic #2 SMP Sun Apr 15 07:36:31 UTC 2007 i686 GNU/Linux

$ cat /proc/asound/version
Advanced Linux Sound Architecture Driver Version 1.0.14rc1 (Tue Jan 09 09:56:17 2007 UTC).

$ cat /proc/asound/cards
 0 [nForce ]: NFORCE - NVidia nForce
                      NVidia nForce with ALC650E at 0xed000000, irq 19

$ cat /proc/asound/timers
  2: : timer
  3: : sequencer
  4: [ 0- 2]: digital audio playback
  5: [ 0- 1]: digital audio capture
  6: [ 0- 0]: digital audio playback
  7: [ 0- 0]: digital audio capture
  8: [ 0] : control

$ cat /proc/asound/oss-devices
No such file or directory

$ cat /proc/asound/devices
G0: system timer : 4000.000us (10000000 ticks)
P0-0-0: PCM playback 0-0-0 : SLAVE
P0-0-1: PCM capture 0-0-1 : SLAVE
P0-1-1: PCM capture 0-1-1 : SLAVE
P0-2-0: PCM playback 0-2-0 : SLAVE

$ cat /proc/asound/pcm
00-02: Intel ICH - IEC958 : NVidia nForce - IEC958 : playback 1
00-01: Intel ICH - MIC ADC : NVidia nForce - MIC ADC : capture 1
00-00: Intel ICH : NVidia nForce : playback 1 : capture 1

$ lsmod | grep snd
snd_intel8x0 34204 2
snd_ac97_codec 98336 1 snd_intel8x0
ac97_bus 3200 1 snd_ac97_codec
snd_pcm_oss 44544 0
snd_mixer_oss 17408 1 snd_pcm_oss
snd_pcm 79876 3 snd_intel8x0,snd_ac97_codec,snd_pcm_oss
snd_seq_dummy 4740 0
snd_seq_oss 32896 0
snd_seq_midi 9600 0
snd_rawmidi 25472 1 snd_seq_midi
snd_seq_midi_event 8448 2 snd_seq_oss,snd_seq_midi
snd_seq 52592 6 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event
snd_timer 23684 2 snd_pcm,snd_seq
snd_seq_device 9100 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq
snd 54020 14 snd_intel8x0,snd_ac97_codec,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_seq_oss,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
soundcore 8672 1 snd
snd_page_alloc 10888 2 snd_intel8x0,snd_pcm